1. Field of the Invention
The present invention relates to network communications and, more particularly, to methods and systems for establishing voice communications. The invention is particularly useful in the context of delivering voice communications to a wireless voice/data terminal such as a 3G mobile phone for instance. However, aspects of the invention can be advantageously applied in other scenarios as well.
2. Description of Related Art
In certain communication systems, a client station may be precluded from engaging in both voice communication and data communication at once. This restriction occurs, by way of example, in some wireless communication systems.
For instance, a 3G mobile station (or, more generally, wireless terminal) may be capable of engaging in a traditional circuit-switched voice call and may also be capable of engaging in packet-data communications. However, in order to preserve air interface bandwidth or for other reasons, the network (and perhaps the mobile station itself) may be set to prevent the mobile station from concurrently having both (i) a radio link over which the mobile station would engage in a voice call and (ii) a radio link over which the mobile station would engage in packet-data communications. Therefore, while the mobile station is engaged in a voice call, the mobile may be unable to send or receive packet-data. And while the mobile station is actively engaged in a packet data session, the mobile station may be unable to place or receive a circuit-switched voice call.